Holding device



June 22, 1954 H. c. WARNER 2,681,597

HOLDING DEVICE Filed May 26, 1949 2 Sheets-Sheet l g IllI IN/ENTOR. d )Wm may wJune z2, 1954 H; C, WARNER 2,681,597

HOLDING DEVICE Filed May 2e, 1949 2 sheets-sheet 2 INVEN TOR.

VM@ @am BY @maf-JM@ Patented June 22, 1954 HOLDING DEVICE Homer C. Warner, Cleveland, Ohio, assignor to The Lees-Bradner Company, Cleveland, Ohio, a corporation of Ohio Application May 26, 1949, Serial No. 95,542

Claims.

This invention relates to a holding device which is particularly applicable to machine tools.

An object of the invention is to provide an improved holding device Which will be very simple in operation.

Another object is to provide an improved holding device which will hold articles very accurately in position.

Another object is to provide an improved holding device which may be operated with little effort.

Another object is to provide an improved holding device which will provide a rm and positive support.

Another object is to provide an improved holding device which will be composed of few and simple parts.

Another object is to provide an improved holding device which will be extremely rugged in construction.

Another object is to provide an improved holding device which may easily and economically be manufactured.

Another object is to provide an improved holding device which may easily be applied to machine tools of various types.

The invention will be better understood from the description of one practical embodiment thereof, illustrated in the accompanying drawings, in which Figure 1 is a plan view of a type of steady rest embodying my invention, this rest being especially designed for use on vertical hobbing machines,

Figure 2 is a transverse sectional view of the rest of Figure ltaken on a plane parallel to and below that of Figure 1 at the level indicated by the line II-II of Figure 3,

Figure 3 is a side elevational view taken on the line III-III of Figure 1,

Figure 4 is a fragmentary end elevational view taken on the line IV--IV of Figure 1, and

Figure 5 is a fragmentary transverse sectional view taken on the line V'-V of Figure l.

While the device is shown as designed for use on vertical hobbing machines and for holding a steady rest for cylindrical pieces, it will be obvious as the description proceeds that it may be used on many other types of machine tools and` that it may be placed in other positions than those shown, as the various devices to which it is applied may require, without any essential modification of its working parts.

In the form illustrated, vthe device is supported on a bracket I having bearing surfaces 2, 3, 4 and 5 arranged to locate the bracket upon the part of the` tool to which it is applied. ln the form illustrated,` these surfaces are arranged toengage the verticaltail stockl ways of the hobbing machine. To these ways the bracket may be secured in any desired manner, as by a bolt passing through an aperture 6 through the bracket.

Fixedto the outer vertical face of the bracket, as by machine screws I, is a generally channelshaped block or frame consisting of web 8 and parallel flanges 9 and I0. The open side of the channel-shaped frame is closed by a plate or cover II, secured to the flanges by machine screws I2, so that a horizontal generally rectangular space is provided within the frame, this being somewhat enlarged centrally thereof, as indicated at I 3, by the cutting away or reduction in thickness of the iianges 9 and le, for a purpose which will become apparent as the description progresses.

To permit access to the machine screws l, perforations I4 are formed through flange I0, and to exclude dirt from entering these perforations. their outer ends are counterbored and closed by expansible plugs I5.

Journaled in the cover II is a bushing I6 through which passes a shaft I'I, the shaft being shown as keyed to the bushing by a Woodruff key I8.

Formed unitarily with the shaft I1 is a cam I9, which, as best seen in Figure 2, is a single lobed cam having a dwell 2i! at its minimum radial distance froml the axis of its shaft and another dwell 2l at its maximum radial distance therefrom, these both being of substantial extent and joined by generally spiral surfaces.

The shaft I'l extends beyond the cam and is provided on its end remote from the bushing I6 with a thread 22, which engages the internaly thread of a generally gland shaped bushing 23 tting into an aperture in web 8 of the frame.

The bushing 23 is held against rotation by a machine screw 24, and its axial position within the aperture of web B is controlled by this machine screw and a set screw 25, these both passingk through the flange portion of the gland shaped bushing 23, the set screw 25 having threaded engagement therewith.

Longitudinally slidable within the channelshaped frame is a slide or crosshead consisting of two rectangular ends 26 and 2'! which substantially fill the space within the frame and are joined by a narrower central portion 28 formed unitarily with these ends 2e and 2l..

This central portion 23 has an elongated slot 29 through which shaft I'I extends, and which permits the slide to travel a limited distance without interference with the shaft.

Block 2l has formed in it an aperture extending generally perpendicularly to the axis of shaft I'I, the outer portion of the aperture being enlarged and threaded to receive the threaded head' 30 of a bearing shoe or abutment 3|, and also to receive a short set screw 32 for locking the threaded portion 30 in adjusted position. It will be noted that the shoe 3| bears upon the right hand side of cam I9 as shown in the drawings.

Rectangular end 26 of the slide is provided with an aperture, substantially in alignment with that in end 2l, shown as having an enlarged counterbored portion in which slides the hollow cylindrical end 33 of a second bearing shoe or abutment 34, engaging the side of cam I9 diametrically opposite to abutment 3l.

Within and extending beyond the hollow of head 33 is a helical compression spring 35, the

outer end of which bears upon the work-supporting shoe 36, this shoe being fixed to end 26 by machine screws 31.V

'I'he outer end of shoe 36 is formed into a shape for engaging the work piece, shown in the drawings as a semi-cylinder having a lining 38 of bearing material which actually contacts with the work piece W.

The outer end of shaft I1 is threaded as indicated at 39 for the reception of a nut 46, which retains a lever or crank `4 I, provided with a handle 42, the lever being secured to bushing I6 to rotate therewith by a pin 43, the pin being selectively engageable with any of a plurality of circularly arranged holes in the bushing so that the handle may be set in any desired angular position for convenient manipulation, by simply loosening the nut 40.

The operation of the device is as follows:

With the parts assembled asV shown in the drawings, the operator rotates the handle in a counterclockwise direction as seen in Figure l, substantially half a revolution from the position in which it appears in this figure, which swings the lobe of the cam to the right, moving the slide 2S, 21, 28 to the right and retracting the shoe 36 from the work piece W.

After replacing the work piece, he rotates the handle in a clockwise direction, returning it to the position in which it is shown in the drawings. This swings the cam to the position shown in Figure 2, the spiral portion of the cam bearing upon abutment 34 and moving the slide and associated parts to the left, so that the shoe 36 engages the new work piece W.

Should the work piece be slightly oversize, pressure of the shoe upon it will compress the spring 35, permitting the slide to travel a slightly shorter distance to the left and thus compensates for such variation in size.

The latter part of this clockwise rotation of the shaft I'I causes the threads at 22 to draw the shaft I1 to the right (as seen in Figure 5) through the engagement of these threads with the bushing 23, and this in turn draws the bushing I8 toward and against slide portion 28, the increased pressure and consequent friction between this slide portion and the bushing serving as a friction brake to lock the parts in position.

Obvously this friction brake is released when the operator again moves the handle in a counterclockwise direction, and due to the substantial extent of thel dwells 26 and 2l, this braking action is entirely eliminated before abutments 3l and 34 are engaged by the interdwell portions of the cam which move the slide.

While I have described the illustrated embodiments of my invention in some particularity, obviously many other embodiments, variations, and modifications will readily occur to those skilled in this art, and I do not, therefore, limit myself to the precise details shown and described herein, but claim as my invention all embodiments, modifications and variations coming within the scope of the appended claims.

I claim:

'1. A holding device comprising a frame having guide ways, a slide movable along the guide ways, a rotatable cam having a substantial dwell engaging the slide, rotating means connected to said cam for rotating the same, locking means actuated by said rotating means while a portion of the dwell of the cam is in engagement Vwith the slide, the slide having opposed abutments engaging opposite sides of the cam, and resilient means interposed between one of said abutments and said slide.

2. A holding device comprising a frame having guide ways, a slide movable along the guide ways, a rotatable cam having a substantial dwell engaging the slide, rotating means connected to said cam for rotating the same, locking means actuated by said rotating means while a portion of the dwell of the cam is in engagement with the slide, the slide having opposed abutments engaging opposite sides of the cam, and resilient means interposed between one of said abutments and said slide, the other abutment being adjustably fixed in and carried by the slide.

3. A holding device comprising a frame having guide ways, a slide reciprocable in said guide ways, a shaft journalled for rotary movement in the frame, a cam carried by the shaft and engaging the slide, said slide having an elongated opening therein for receiving said shaft, bushings in the frame for supporting said shaft, and threaded means carried by the shaft, ,one of said bushings having a slide-engaging surface for frictionally engaging the same to lock the slide in the frame upon rotation of the cam and the shaft to a predetermined position.

4. A holding device comprising a frame having guide ways, a slide reciprocable in said guide ways, a shaft journaled for rotary movement in the frame, a cam carried by the shaft and engaging the slide, said slide having an elongated opening therein for receiving said shaft, bushings in the frame for supporting said shaft, threaded means carried by the shaft, one of said bushings having a slide-engaging surface for frictionally engaging the same to lock the slide in the frame upon rotation of the cam and the shaft to a predetermined position, said threaded means carried by the shaft comprising a bushing threaded on an end of the shaft and movable axially in said frame, and means carried by said bushing to position the same axially with respect to the frame.

5. A holding device comprising a frame having guide ways, a slide movable along the guide ways, a rotatable cam having a substantial dwell engaging the slide, rotating means connected to said cam for rotating the same, and locking means actuated by said rotating means while a; portion of the dwell of the cam is in engagement with the slide, said locking means Vincluding a cam shaft, bushings in the frame for supportingv said shaft rotatably therein, one of said bushings having a flat frame engaging surface for frictionally engaging the same whereby to lock said slide in a predetermined' position in said frame.

References Cited in the le of this patent UNITED STATES PATENTS 379,874 Germany Aug. 29, 1923 

